Fabric-reinforced polymer materials are a category of composite materials that use fabric materials to mechanically enhance the strength and elasticity of the polymer materials. For example, rubber articles such as tires, hoses, and belts are composite materials of various natural and synthetic rubber compositions reinforced with different reinforcing materials such as reinforced fibers made from synthetic fabric materials.
When forming the composite materials, it is desirable to achieve good adhesion between the reinforcing fabric phase and the polymer matrix phase (i.e., the polymer material without fabric reinforcement) to maintain the integrity of the composite material. However synthetic fabrics have difficulty of adhering to the polymer matrix because of their generally smooth polymer surfaces and low surface activity, typically because of their lower polarity and reactivity of the polymer molecules in the fabric material.
To promote the adhesion between the reinforcing fabric phase and the polymer matrix phase, much of the current technology employs adhesives and related applying processes. For example, two adhesive systems are widely used to promote the adhesion between the reinforcing fabric fiber and the rubber compositions in tire industry: the resorcinol-formaldehyde-latex (RFL) coating method where an RFL adhesive is applied to the fabric cord, and the hexamethylenetetramine-resorcinol or hexamethoxymethylmelamine-resorcinol adhesion promoting methods in which an adhesion promotion system is incorporated into the rubber composition.
However, none of the existing technology sufficiently establishes a chemical bonding between the fabric phase and the phenolic adhesive to promote the strong adhesion between the fabric phase and the polymer matrix phase. Therefore, there remains a need in the art to develop an improved method to achieve a better adhesion between the reinforcing fabric phase and the polymer matrix phase. A particular need exists in the rubber industry to provide an improved bonding between the reinforced fabric material and the rubber composition. This invention answers that need.